Secondary batteries may be classified into can-type secondary batteries where an electrode assembly is embedded in a cylindrical-type or rectangular-type metal can, and pouch-type secondary batteries where an electrode assembly is embedded in a pouch of an aluminum laminate sheet.
Especially, since the pouch-type secondary battery uses a pouch case made of a soft sheet material, it has advantages that allow diversification of product forms and facilitate miniaturization.
In general, the pouch-type secondary battery is fabricated through a process of assembling a cell and a process of activating the cell and the like, and in the cell activation process, the cell is mounted onto a certain jig for smooth conduction of current, and processes of charging, discharging and the like are performed under conditions required for the activation. The jig is used for a purpose of testing the performance of a fabricated secondary battery beforehand. Recently, as the application fields of the secondary battery are becoming extremely diverse, cells of various sizes and structures are being fabricated, and in order to activate or test such cells, jigs that are suitable thereto must be used.
A technique related to the jig of the battery cell is disclosed in, for example, Korean Laid-open Patent Publication No. 2008-0068305 and in Japanese Laid-open Patent Publication No. 2007-194216.
Korean Laid-open Patent Publication No. 2008-0068305 proposes a jig for charging and discharging of a plate shape secondary battery, consisting of a first member where an upper electrode terminal portion is located and a second member where a lower electrode terminal portion is located in a state where a battery cell is mounted, and where the members have a combined structure that may be changed in a longitudinal direction of the battery cell. According to this jig for charging and discharging, it is possible to perform charging and discharging for activation of the battery cell regardless of the size of the battery cell or location of the electrode terminal, or test the performance of the battery cell, and minimize damage to the battery cell caused by heat generated in the process of charging and discharging.
Japanese Laid-open Patent Publication No. 2007-194216 relates to a controllable pressing tool of fuel cell, and proposes a controllable pressing jig of a fuel cell group that supplies an optimal contact pressure to the fuel cell group or a fuel cell stack by a controllable pressure source.
Meanwhile, the cell of the pouch-type secondary battery cell requires a pressing jig that is capable of restricting increase of thickness due to expansion of the cell in the activation process. However, a conventional pressing jig is made of heavy metal, which is not easy to use and handle, and is difficult to be applied to an automated process, and therefore needs improvement.